US3643190A

US3643190A - Structure for mounting an electromagnet in an electromagnetically operated switch

Info

Publication number: US3643190A
Application number: US99614A
Authority: US
Inventors: Jordan F Puetz; James E Stallman
Original assignee: Square D Co
Current assignee: Schneider Electric USA Inc
Priority date: 1970-12-18
Filing date: 1970-12-18
Publication date: 1972-02-15
Anticipated expiration: 1989-02-15
Also published as: GB1339855A; CA946030A

Abstract

A structure for mounting an electromagnet in an electromagnetically operated switch. The structure includes a metal shock plate which is mounted on four posts that extend from a front surface of an insulated base whereon the stationary contacts of the switch are mounted. The front face of the shock plate has a mounting surface whereon an elastomeric pad is positioned and four spaced raised fingers which provide support surfaces along opposite sides of the mounting surface. The raised fingers provide a mounting for a pair of L-shaped members that are secured to each other and to the fingers to provide a frame that surrounds a stationary magnet when a rear wall of the magnet is positioned on the elastomeric pad. The magnet has projections on each of its opposite ends which provide a surface whereon elastomeric pads are positioned. The L-shaped members each have one leg resting on the elastomeric pads located on the projections so that the magnet is resiliently mounted on the shock plate. The L-shaped members also have openings therein which receive projections on a magnet coil to position the coil on the magnet and portions which guide the movement of an armature when the electromagnet is energized.

Description

[ 1 Feb. 15, 1972 United States Patent Puetz et al. I

[57] ABSTRACT A structure for mounting an electromagnet in an electromagnetically operated switch. The structure includes a metal [54] STRUCTURE FOR MOUNTING AN ELECTROMAGNET IN AN ELECTROMAGNETICALLY OPERATED SWITCH [72] Inventors:

shock plate which is mounted on four posts that extend from a front surface of an insulated base whe Jordan Puetz M'lwaukee James tacts of the switch are mounted. The

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plate has a mounting surface whereon an elastomeric positioned and four spaced raised fin port surfaces along opposite sides of the mountin The raised fingers provide a mountin members that are secured to each other and to the tin provide a frame that surrounds a stationar rear wall of the magnet is positioned on th The magnet has projections on each of its 0 provide a surface whereon elastomeric The L-shaped members each have on elastomeric pads located on the is resiliently mounted on the sh bers also have openings therein whi magnet coil to position the coil 0 which guide the movement of an armatu tromagnet is energized.

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JORDAN F. PUETZ JAMES E.STALLMAN PATENTEDFEB 15 I972 SHEET 3 BF 3 INVENTOR.

JORDAN F. PUETZ JAMES E. STALLMAN BY 2 Z STRUCTURE FORMOUNTING AN ELECTROMAGNET IN AN ELECTROMAGNETICALLY OPERATED SWITCH The present invention relates to electromagnetically operated switching devices and particularly to a structure for supporting an electromagnet in an electromagnetically operated switch.

Electromagnetic switching devices, of the type with which the present invention is concerned, are commonly known as contactors and are furnished as switching units of various sizes, having ratings which are normally in accordance with the standards promulgated by the National Electrical Manufacturers Association, commonly known as NEMA. Among the commercial requirements which a contactor is required to satisfy are that the contactor must be constructed so it can be easily mounted and wired on a panel and that the parts of the contactor be arranged so it is easy to inspect and replace the various components, such as the switching contacts and coil of the contactor, while the contactor is wired on the panel.

In larger sized contactors, i.e., NEMA Size 5 contactors which are rated to carry 300 amperes or less, a magnet of considerable size and weight is required to exert the force required to cause a proper engagement between the movable and the stationary contacts of the contactor. Thus, from a design standpoint, the relatively heavy magnet in the contactor should be located as close as possible to the panel. However, present commercial requirements dictate that the most desirable form of a contactor should have its line or supply 'wire connections at the top of the device and the load wire connections at the bottom of the device to provide an arrangement which is commonly termed as straight-thru wiring. Further, the commercial requirements dictate that the wire connecting terminals be freely accessible and located as close to the panel aselectrical clearance requirements will permit. Thus, if a contactor is to have a simple economical construction, a minimum size for its rated capacity, and is to include a straight-thru wiring feature, the design requirements dictate that it is impracticalto mount the magnet portion of the ,contact directly on the panel. Therefore, in the device according to the present invention, the magnet is carried forwardly of the base which supports the stationary contacts and wire connecting terminals so that the device may be readily wired on the panel with straight-thru wiring and may be readily disassembled to permit the movable and the stationary contacts to be serviced. Further, in the contactor according to the present invention, the magnet armature is arranged to move toward the base when the electromagnet is energized to provide an economical simplified contactor structure. As the contactor construction herein described is intended for the larger size NEMA rated devices, it necessarily includes a relatively heavy armature which generates a considerable impact shock when the electromagnet is energized. The undesirable effects of the impact shock are minimized by a structure which includes a shock plate which supports the electromagnet and is mounted on four sturdy posts that extend from the molded base of the contactor. The four posts have inserts molded therein which extend to the mounting panel so that the shock accompanying the engagement between the annature and stationary magnet part is directly transmitted to the mounting panel and in effect bypasses the base. Further, a molded barrier which encloses the contacts so as to isolate the poles of the contactor from each other and ground is suspended from the shock plate so as to be out of engagement with the base. Thus the shock is not transmitted through the barrier to the base and the inspection and servicing of the contact structure is readily accomplished by merely removing the screws securing the shock plate to the posts so that the entire assembly, including the electromagnet and barrier, may be removed to make the contacts of the structure readily accessible. The structure for mounting the electromagnet on the shock plate includes a pair of members which are secured to each other and to fingers that extend from the forward surface of the shock plate. The pair of members provide a rectangular frame that surrounds the stationary magnet and provide an arrangement whereby the coil may be readily removed for replacement purposes. The members further provide a guide for the armature and a structure for resiliently supporting the stationary magnet so the magnet has a limited movement on the shock plate to reduce the noise when pole faces of the armature and magnet are in engagement with each other and the shock which accompanies the impact between the armature and the stationary magnet when the electromagnet is initially energized.

It is an object of the present invention to resiliently mount an electromagnet structure of a contactor on a metal plate which is supported on posts which extend forwardly of a molded base carrying the stationary contacts of the contactor with a means that include a pair of L-shaped members that are secured to each other and to fingers which extend from a front surface of the metal plate.

Another object is to resiliently mount an electromagnet structure of a contactor on a metal plate with a means that includes a pair of L-shaped members that provide a frame that is spaced forwardly of the front surface and surrounds a stationary magnet portion of the electromagnet when the members are secured to fingers extending forwardly of the front surface and to provide the members with openings which receive projections on a magnet coil portion of the electromagnet to position the coil on the magnet and portions which guide the armature portion of the electromagnet during the movement of the armature toward the stationary magnet.

An additional object is to mount an electromagnet structure of a contactor on a metal plate with a means that includes a pair of L-shaped membersthat provide a frame that is spaced forwardly of the front surface of the metal plate and engages side and end wall portions of a stationary magnet portion of the electromagnet to position the magnet on the plate and to provide the members with openings which receive projections on a magnet coil portion of the electromagnet to position the coil on the magnetand portions which guide the armature portion of the electromagnet during its movement toward the magnet and to provide an elastomeric pad between a rear surface on themagnet and the metal plate and elastomeric pads between projections on the magnet arm portions of the pair of members so the magnet is resiliently mounted on the plate to have limited movement to reduce the shock and the noise generated between the armature and magnet when the coil is energized.

A still further object is to resiliently mount an electromagnet structure of a contactor on a metal plate which is supported on posts which extend forwardly of a molded base carrying the stationary contacts of the contactor with a means that includes a pair of L-shaped members that provide a frame that is spaced forwardly of the front surface of the plate and engages side and end wall portions of a stationary magnet portion of the electromagnet to position the magnet on the plate and to provide the members with openings which receive projections on a magnet coil portion of the electromagnet to position the coil on the magnet and portions which guide the armature portion of the electromagnet during its movement toward the magnet and to provide an elastomeric pad between a rear surface on the magnet and the metal plate and elastomeric pads between projections on the magnet and arm portions of the pair of members so the magnet is resiliently mounted on the plate to have limited movement to reduce the shock and the noise generated between the armature and magnet when the coil is energized and to maintain the position of the coil on the magnet by resilient supports that are carried by a cover portion of the contactor.

Further objects and features of the invention will be readily apparent to those skilled in the art from the specification and appended drawings illustrating certain preferred embodiments in which:

FIG. 1 is an end view of an electromagnetically operated switching device incorporating the features of the present invention.

FIG. 2 is a front'view of the switching device in FIG. 1 with a cover, an armature and a magnet coil removed to illustrate a mounting for a stationary magnet portion of the device.

FIG. 3 is a view of the device in FIG. 2 with the magnet coil installed. I

FIG. 4 is a perspective view of the magnet coil and a pair of L-shaped members which are included in the switching device in FIG. 1.

FIG. 5 is an exploded view showing in perspective a metal mounting plate, a stationary magnet part, a pair of assembled L-shaped members, a magnet coil, an armature assembly and a cover which are included in the switching device in FIG. 1.

For the convenience in description, the electromagnet switch on contactor is described herein as disposed in a horizontal position when the contactor is mounted on a front wall of a vertical panel, the parts of the contactor being described in relation to this position. Accordingly, the terms front and rear, upper and lower, vertical and horizontal and the like are not absolute but merely define more readily the relative positions of portions of the parts and their relative positions to each other when the contactor is mounted on a panel.

Referring to FIG. 1 of the drawings, an electromagnetic switch assembly is shown as having a plurality of components that are stacked one upon the other. The components of the assembly 10 include a metal mounting plate 12, an insulating base 14, an insulating barrier 16, a shock plate 18, an electromagnetic assembly 20, a cover 22 and a movable contact carrier 24.

As disclosed in an application for U.S. Pat. having a Ser. No. 996I3, concurrently filed herewith, the contactor structure is arranged so that the shock plate 18 rests on four posts which extend forwardly of the base 14. The shock plate 18 mounts the barrier 16 in spaced relation to the base 14 to provide easy access to the movable and stationary contact structures of the device and transmits the magnet closing shock directly through the four posts to the mounting plate 12. Similarly, the details of the cover 22 and arrangement for connecting the armature of the electromagnetic assembly to the contact carrier 24 are respectively shown in applications for U.S. Pat., Ser. Nos. 99573 and 99574, which are similarly concurrentlyfiled herewith.

As shown in FIGS. 1 and 2, the metal mounting plate 12 is formed as a stamped metal part to provide a means to secure the switch assembly 10 to a vertical panel and the like, not shown. When the plate 12 is secured to the panel, an edge 26 becomes the bottom edge of the plate 12 and a surface 28 the front surface of the plate 12. The plate 12 has a pair of rearwardly extending indentations 30 along its bottom edge 26 that provide a pair of spaced mounting feet having opening therein. The plate 12 also has an indentation 32 at its top edge which provides an elongated mounting foot having an opening therein which, together with the indentations 30, are provided forthe purpose of securing the plate 12 to a vertical panel.

The switch 10 is a three pole device, in that it is capable of completing and interrupting a three phase circuit when the switch 10 is actuated and deactuated. To enable the switch 10 to function as a three-pole device, the base 14 and the barrier 16 are formed of a molded insulated material having arc suppressing capabilities and cooperate with each other to provide three compartments which extend parallel between the top and bottom of the switch 10. Positioned in each compartment is a set of stationary contacts and a movable contact in a manner disclosed in an application for U.S. Pat., Ser. No. 99612, concurrently filed herewith. Extending into the material of the base forwardly of a rear surface 34 and to the sidewalls of the base 14 is a slot. The slot is centered on a centerline equidistant between a top wall 36 and a bottom wall 38 of the base 14 and is exposed to each of the compartments by a passage. Positioned on opposite sides of the centerline of the base in each of the compartments is a pair of stationary contact assemblies which are respectively connected to terminal members 40. The terminal members 40 are arranged to accept the bared end of a wire conductor and are electrically connected to the stationary contacts within the compartments. The movable contact carrier 24 is generally U-shaped having a bight or body portion received in the slot, and a pair of arm portions 42 extending extemally of the sidewalls of the base 14 and barrier 16. The arm portions 42 are connected to an armature 44 of the electromagnetic assembly 20 and are moved rearwardly toward the plate 12 when the electromagnet assembly 20 is energized. At least one pair of compression springs 46 positioned between a rear wall of the bight portion on the contact carrier 24 and the plate 12 cause the movable contact carrier 24 to be positioned forwardly when the electromagnetic assembly 20 is deenergized. Extending from the bight portion of the contact carrier 24 into each of the compartments is a projection which provides a mounting for a movable contact and the spring biased releasable retainer for the movable contact in a manner fully disclosed in the application for U.S. Pat. Ser. No. 99612, supra.

Extending forwardly from a front surface on the base 14 are four spaced posts 48 each of which has a front surface 50 that is spaced from the remaining front surface portions of the base 14. The posts 48, which are more clearly described in the application for Us. Pat. Ser. No. 99613, supra, have metal inserts embedded therein that have a rear end flush with a rear surface 34 of the base 14 and extend substantially throughout the molded material of the posts 48. The inserts have threaded bores at their opposite ends which are respectively used to mount the base 14 on the metal mounting plate 12 and receive screws 52 at their forward end which mount the shock plate 18 on the front surfaces 50.

The shock plate 18 is formed as a metal plate having a thickness so it will resist deformation when it is mounted on the surfaces 50 provided by the four spaced posts 48. The posts 48 extend from the front surface of the base 12 so two of the posts 48 are on each side of a plane that is normal to and passes through the horizontal center of the base 14. As most clearly seen in FIG. 5, the shock plate l8 has a front surface 54 and a rear surface 56 and four openings 58 located therein to be aligned with the threaded bores in the four posts 48 when the rear surface 56 is positioned on the front surfaces 50. The shock plate 18 is mounted on the front surface 50 in spaced relation to the front surface of the base by the four screws 52 which pass through the openings 58 and are threaded into the inserts in the posts 48. The shock plate 18 has an additional four spaced openings 60 which receive four screws 62 to mount the barrier 16 on the rear surface 56. The barrier 16 has suitable inserts molded therein to receive the screws 62 so as to be suspended on the shock plate 18 with all the portions of its rear surface in spaced relation to the front surface portions of the base 14.

The front surface of the barrier 16 and the rear surface 56 of the shock plate 18 are shaped relative to each other so that the only areas of contact existing between the barrier 16 and shock plate 18 occur where the portions of the shock plate 18 surrounding the openings 58 engage the portions of the barrier 16 which surround the inserts receiving the screws 62. Thus in effect the barrier 16 is suspended in spaced relation to the shock plate 18.

A rectangularly shaped central portion of the front surface 54-that extends between the opposite sidewalls of the barrier provides a mounting surface 68. The mounting surface 68 is rectangular in shape. Extending upwardly and downwardly from opposite sides of the mounting surface 68 are portions 70 and 72 wherein the

openings

58 and 60 are located. The portions 70 and 72 are winglike in shape and extend from opposite sides of the mounting surface 68 so the front surface of the mounting surface 68 is rearwardly of the front surfaces of the portions 70 and 72 whereby the mounting surface 68 simulates a rearwardly depressed portion in the front surface 54. Extending upwardly at the ends of the upper side of the rectangular mounting surface 68 are a pair of forwardly and upwardly extending fingers 74. Similarly extending downwardly at the ends of the lower side of the mounting surface 68 are a pair of forwardly and downwardly extending fingers 76. The

fingers

74 and 76 each have an inclined portion 78 extending forwardly from the front surface to present support surface portions 80 that are spaced from each other and extend in a plane that is parallel and spaced forwardly of the mounting surface 68. Each of the support surfaces 80 has a threaded opening 82 therein. A pad 84, formed of a suitable elastomeric material, such as Buna N rubber, is secured on the mounting surface 68 to have its front surface substantially flush with the front surfaces of the portions 70 and 72.

In addition to the armature 44, the electromagnet assembly includes a stationary magnet part 86 and a magnet coil 88. The stationary magnet 86 in the form shown is E-shaped and formed of a stack of E-shaped laminated magnet iron pieces which are positioned between a pair of E-shaped nonmagnetic iron plates which are secured together by strategically located rivets to provide a unitary assembly in a manner well known to those skilled in the art. The magnet 86 has a rear wall 90, a pair of

sidewalls

92 and 94, a pair of

end walls

96 and 98 and is shaped to provide

poles

99 and 101 at its opposite ends having forwardly facing pole faces 100 and 102 thereon and a center pole 103 that is located centrally between the

poles

99 and 101 which provides a center pole face 104. The

poles

99 and 101 are suitably grooved to receive shading coils 106. The

end walls

96 and 98 are respectively shaped to provide a projection 107 that presents forwardly facing support surfaces at the opposite ends of the magnet 86 whereon

pads

112 and 114 are respectively positioned. The

pads

112 and 114 are formed of a suitable elastomeric material, such as Buna N rubber, and are located on the support surfaces on the projections 107 so as to extend in a plane that is spaced forwardly of the rear wall 90.

A means for mounting the stationary magnet 86 on the elastomeric pad 84, positioning the magnet coil 88 on the stationary magnet 86 and guiding the annature 44 during its movements includes a pair of

members

116 and 118 which are secured to each other and to the front surface of the shock plate 18, as will now be described. The

members

116 and 118 are identical and are each formed as a metal part to have a L- shape to have a first leg portion 120 and a second leg portion 122 which are arranged to provide a rectangular frame when an end portion 124 on the free end of the leg 120 is secured to an end portion 126 on the free end of the leg 122. The end portions 124 are formed to overlay the end portions 126 in a manner so the rear surfaces on the members extend in a common plane. The

end portions

124 and 126 have openings 128 therein and the legs 120 have an opening 130 therein. The

openings

128 and 130 are located in the

members

116 and 118 so as to be aligned with the threaded openings 82 when the rear side of the

members

116 and 118 are positioned on the four support surfaces 80 provided by the two pairs of

fingets

74 and 76 to permit the

members

116 and 118 to be secured to the shock plate 18 by screws 132 which are threaded into the openings 82.

The

members

116 and 118 when secured to the shock plate will provide a frame 134 which is spaced forwardly of the shock plate and surrounds the magnet 86. The leg portions 120 on the

members

116 and 118 have a pair of projections 136 which engage the

sidewalls

92 and 94. Similarly, the leg portions 122 on the

members

116 and 118 each have a projection 137 extending to engage the

end walls

96 and 98 that are disposed forwardly of the

pads

112 and 114 to position the magnet 86 against movement in a direction parallel to the mounting surface 68. When the

members

116 and 118 are mounted on the

fingers

74 and 76, the rear surface on the leg portions 122 will be positioned against the forward facing surface on the

elastomeric pads

112 and 114 so the magnet 86 will be resiliently mounted against movement in a direction vertical to the mounting plate 12 by the elastomeric pads 84 and the

elastomeric pads

112 and 114. The legs 120 of the

members

116 and 118 each have a pair of openings 138 therein and the legs 122 of the

members

116 and 118 each have a portion 140 that extends forwardly from the portion whereon the projection 137 is formed. The function of the openings 138 and the portions 140 will be hereinafter described.

The magnet coil 88 is formed as an encapsulated molded body which has a coil winding embedded therein connected to input terminals 142 which are externally accessible on a front side 144 of the coil 88. The molded body forming the coil 88 has arear side 146 and a rectangularly shaped passage 148 extending between the rear side 146 and the front side 144. The passage 148 is sized to receive the center pole 103 of the magnet. Additionally, the coil has four mounting pads located at the comers of a rectangle extending from its rear surface. These pads, which are located at the opposite corners of the rectangle, have projections extending therefrom, two of which are indicated by a numeral 150 in FIG. 4. The projections 150 have tapered ends and are located on the rear side 146 to be received in the openings 138 to position the coil 88 against movement in a plane parallel to the mounting plate 12 while the pads engaging the front surface of the

members

116 and 118 position the coil against rearward movement in the switch 10. Thus the

members

116 and 118 position the coil 88 against movement in any of three directions. The coil.88 is formed so as to surround the center pole 103 and be received in the spaces between the center pole 103 and the

poles

99 and 101.

The details of the armature 44 and its attachment to the movable contact carrier 24 are clearly set forth in the U.S. Pat. application, Ser. No. 99574. The armature 44 includes a stack of laminated magnet iron pieces 152 which are positioned between a pair of nonmagnetic metal parts 154. The laminated pieces'152 and the parts 154 are secured together by strategically located rivets 156 and are shaped to provide pole faces 158 and 160 at the opposite ends of the metal pieces 152 which engage the pole faces 100 and 102 respectively when a center pole face 162 is aligned with the center pole face 104. Secured at the opposite ends of the armature are a pair of molded members 164. The members 164 are secured to the free end of the arm portion 42 of the movable contact carrier 24 in a manner disclosed in application for U.S. Pat. application, Ser. No. 99574, supra. Each of the molded members 164 has an arcuately shaped surface 166 positioned adjacent the portions 140 on the

members

116 and 118. The portions 140 have surfaceareas 168 which are arranged to be engaged by portions of the arcuately shaped surface 166 to guide the movement of the armature 44 along an axis that is parallel to the top and the

bottom walls

36 and 38 and perpendicular to the surface 28.

Extending forwardly from the front face of the barrier are four posts 170, each of which has a front surface in a plane that is spaced forwardly and parallel to the front side 144 of the coil 88. The posts 170 each have a threaded insert embedded therein which are exposed at the front end of the posts 170 and are located to provide guide surfaces 172 which are located to be engaged by surface portions on the upper and lower sides of the members 164 to guide the armature 44 during its movements. The cover 22, which is more fully described in the application for U.S. Pat, Ser. No. 99573, is formed from a metal piece as a U-shaped channel having a pair of outwardly extending flanges 174 at the ends of the arms 176 forming the U-shaped channel. The flanges 174 have openings therein to receive screws 178 which secure the cover 22 to the front surfaces of the posts 170 when the screws 178 are threaded into the inserts within the posts 170. Each of the flanges 174 has an opening therein which positions a springbiased plunger 180 which has its rear end positioned against the front side 144 of the coil 88 when the cover 22 is secured on the posts 170. The plungers 180 carried by the cover 22 resiliently maintain the coil 88 against movement in a forward direction from its position on the members 1 16 and 118. Thus it is apparent that the shock plate 18 and the

members

116 and 118 provide a mounting for the stationary magnet 86 without requiring mounting feet or cars on the stationary magnet 86 which are conventionally used in devices of the type herein described. Further, upon energization of the magnet coil 88, the shock accompanying the engagement between the pole faces 100 and 102 with the pole faces 158 and 160 will be initially absorbed by the elastomeric pad 84 and then transmitted through the

fingers

74 and 76 to the shock plate 18. Further, when the magnet coil 88 is initially energized, the stationary magnet 86 will tend to move toward the armature 44 while the armature 44 is being attracted toward the stationary magnet 86. The

elastomeric pads

112 and 114 permit a slight movement of the stationary magnet 86 toward the armature 44 to further dampen the shock when the pole faces on the armature 44 engage the pole faces on the stationary magnet 86.

Further access to the coil may be readily obtained by removing the four screws 178 so the cover 22 may be detached from the barrier 16 and removing two screws 182 which extend through the members 164 and are threaded into inserts which are embedded in the end portions of the arms 42 so the armature 44 may be detached from the contact'carrier 24. The detached cover 22 and armature 24 will expose the coil 88 so it can be removed from its position on the

members

116 and 118 so the switch assembly will appear as in FIG. 3. When the coil 88 is replaced in a manner previously described, the switch assembly will appear as in FIG. 2 and the replacementof the armature 24 and cover 22 as described will complete the reassembly of the switch assembly 10.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In, an electromagnetically operated switch, the combination comprising: an insulating base having a front surface, a metal shock plate having a rear surface mounted on the base in spaced relation to the front surface of the base, and a front surface providing a mounting surface, an electromagnet ineluding a stationary magnet, a movable armature and a magnet coil, and a means for mounting the stationary magnet on the mounting surface, positioning the magnet coil on the stationary magnet and guiding the armature in its movement into engagement with the stationary magnet, said means including a pair of members secured to each other and to the front surface of the shock plate to provide a rectangular frame that is spaced forwardly of the mounting surface and surrounds the stationary mag'net, said members each having an opening therein receiving a projection on the coil for positioning the coil on the stationary magnet and a surface engaging a portion that is movable with the armature to guide the armature during its movement.

2. The combination as recited in claim 1 wherein the stationary magnet has a pair of sidewalls, a pair of end walls, a rear wall, a front end providing a pair of forwardly facing pole faces at the opposite ends of the front end and a forwardly facing support surface extending outwardly from each end wall, the pair of members that provide the frame are L-shaped each have a first leg portion wherein the coil positioning opening is located and a second leg portion providing the surface for guiding the armature movement and wherein the combination includes an elastomeric pad that is positioned between the rear wall on the magnet and the mounting surface on the shock plate, and an elastomeric pad on each forwardly facing support surface on the magnet that is positioned between the forwardly facing support surface and the second leg portion of one of the pair of L-shaped members.

3. The combination as recited in claim 2 wherein the mounting surface on the shock plate has a pair of opposite sides and a pair of raised spaced support surfaces extend from the front surface of the shock plate adjacent each of the opposite sides of the mounting surface.

4. The combination as recited in claim 3 wherein each of the support surfaces are provided by struckout portions in the shock plate that extend forwardly from the front surface of the shock plate.

5. The combination as recited in claim 4 wherein each of the struckout portions includes a portion that is inclined relative to the mounting surface and a support portion that extends in a plane that is parallel and spaced forwardly of the mounting surface and each of the support portions has a threaded opening therein which receives a screw to secure the pair of L-shaped members to each other and to the front surface of the shock plate.

6. The combination as recited in claim 5 wherein the shock plate is mounted on four posts that extend forwardly of the front surface of the base.

7. The combination as recited in claim 6 wherein the first and the second leg portions have projections extending therefrom which respectively engage the side and the end walls of the stationary magnet.

8. The combination as recited in claim 2 wherein the shock plate is mounted on four posts that extend forwardly of the front surface of the base.

9. The combination as recited in claim 2 wherein the first and the second leg portions have projections extending therefrom which respectively engage the side and the end walls of the stationary magnet.

10. The combination as recited in claim 1 wherein the stationary magnet has a pair of sidewalls, a pair of end walls, a rear wall, a front end providing a pair of forwardly facing pole faces at the opposite ends of the front end and a forwardly facing support surface extending outwardly from each end wall, the pair of members that provide the frame are L-shaped each have a first leg portion wherein the coil positioning opening is located and a second leg portion providing the surface for guiding the armature movement and wherein the combination includes an elastomeric pad that is positioned between the rear wall on' the magnet and the mounting surface on the shock plate.

Claims

1. In an electromagnetically operated switch, the combination comprising: an insulating base having a front surface, a metal shock plate having a rear surface mounted on the base in spaced relation to the front surface of the base, and a front surface providing a mounting surface, an electromagnet including a stationary magnet, a movable armature and a magnet coil, and a means for mounting the stationary magnet on the mounting surface, positioning the magnet coil on the stationary magnet and guiding the armature in its movement into engagement with the stationary magnet, said means including a pair of members secured to each other and to the front surface of the shock plate to provide a rectangular frame that is spaced forwardly of the mounting surface and surrounds the stationary magnet, said members each having an opening therein receiving a projection on the coil for positioning the coil on the stationary magnet and a surface engaging a portion that is movable with the armature to guide the armature during its movement.

10. The combination as recited in claim 1 wherein the stationary magnet has a pair of sidewalls, a pair of end walls, a rear wall, a front end providing a pair of forwardly facing pole faces at the opposite ends of the front end and a forwardly facing support surface extending outwardly from each end wall, the pair of members that provide the frame are L-shaped each have a first leg portion wherein the coil positioning opening is located and a second leg portion providing the surface for guiding the armature movement and wherein the combination includes an elastomeric pad that is positioned between the rear wall on the magnet and the mounting surface on the shock plate.